Qums, Resins, 



510 



[December, 1908. 



valued at 4s. 6d. per lb. in London, the 

 correspond hie; scrap rubber, No. 23, 

 being valued at 2s. 7d. per lb. 



Funtumia Rubber (Funtumia elastica). 



No. 13. " Funtumia elastica. Ire rub- 

 ber ; coagulated by boiling."' Weight 

 If oz. 



A small oval piece of black rubber, 

 clean, well prepared and free from 

 stickiness ; it exhibited fair elasticity and 

 tenacity. 



The following results were obtained 

 on analysis:— 





Rubber as 



Composition 





received. 



dry rubber. 





Per cent. 



Per cent. 



Moisture ... 



... 3-2 





Caoutchouc 



...84-8 



87-6 



Resin 



... 8-7 



9-0 



Proteids ... 



... 2-6 



2-7 



Insoluble matter 



... 0-7 



0-7 



Ash 



... 0-71 



0-73 



This rubber is of very fair quality, 

 although it is not very strong and the 

 percentage of resin is a little high. The 

 specimen was valued at 3s 8d. per lb. in 

 London, 



Rubber op Landolphia Kirkii. 



No. 14. "Landolphia rubber." Weight 

 h oz. 



A very small ball of reddish-brown 

 rubber, which was white internally 

 when freshly cut. The rubber was clean 

 of good quality, and exhibited very 

 satisfactory physical properties. 



The sample was too small for chemical 

 examination or commercial valuation. 



The botanical specimens of the vine 

 which furnished this rubber have been 

 identified at Kew as Landolphia Kirkii, 

 Dyer. 



Balata (Mimusops globosa). 



No, 24, " Balata from Venezuela {Mimu- 

 sops globosa.)" Weight 2| lb. 



A block of balata measuring about 8 

 inches by 3| inches by 3^ inches. 



It was dark grey in colour, fairly 

 clean, hard and very tenacious. The 

 balata had the following composition:— 



Per cent. 



Moisture ... ... 1'8 



Gutta 45-7 



Resin 44'2 



Proteids 3 l 



Insoluble matter ... 5*3 



Ash 1'28 



This sample of balata is of good 

 quality, agreeing well in composition 

 with the average figures of commercial 

 consignments. It was valued at Is. 7|d. 

 per lb. in London. 



Loranthus Rubber. 



No. 25. "Venezuelan Loranthus rub- 

 ber." Weight 1 oz. 



This sample consisted of two pieces 

 of rubber : (1) a thin strip 1 inch by 3 

 inches, with smooth surface, and (2) a 

 thin flat cake with rough surface. 



The rubber was fairly tenacious but 

 exhibited little elasticity. 



The following results were obtained 

 on analysis :— 



Rubber as Composition of 



received. dry rubber. 



Per cent. Per cent. 



Moisture ... 4-7 — 



Caoutchouc ... 54 4 57'1 



Resin ... 17 7 18'6 



Proteids ... 4'1 4-3 



Insoluble matter 19'1 20 



Ash ... 1-70 1-78 



This Loranthus rubber is of inferior 

 quality on account of the high percen- 

 tage of resin and the large amount of 

 insoluble matter present. The sample 

 was too small for trustworthy valuation. 



Conclusions. 



Para Rubber — The investigation has 

 shown that the samples of Para rubber 

 prepared in Trinidad are of good quality 

 and would realise very satisfactory 

 prices in the market. Prom the speci- 

 mens submitted to the Imperial Institute 

 it would appear that the rubber from 

 tree A is a little better than that yielded 

 by tree B, although the difference is 

 only slight. 



Castilloa Rubber. — The two samples 

 of Castilloa rubber, Nos. 10 and 11, from 

 tree growing on land belonging to 

 the Botanical Department, contain an 

 exceptionally high percentage of resin 

 (viz,, 52 and 37 per cent, respectively) 

 for the product of 7^ year old trees. 

 It may, however, be noted that the 

 trees in question are stated to be of 

 small growth owing to the fact that 

 they were planted along with Para trees 

 and the latter had outgrown them. 



The other samples of Castilloa rubber 

 were derived from private estates in 

 Trinidad. Of these. No. 19 contained 

 37'2 per cent, of resin, thus agreeing in 

 composition with No. 11, whereas in the 

 other specimens, Nos. 15, 17, 21, and 

 22, the amounts of resin were much 

 less, ranging from 15 '6 to 23 per cent. 



